This invention pertains generally to electrical and electronic circuitry components and, more specifically, to wire and cable tracing methodologies and devices.
Whether it is the installation of a simple home audio system, a large corporate server network, or the assembly of a sophisticated jet aircraft, wiring systems play a crucial role in insuring proper system functionality. It becomes apparent that if a system were available that could rapidly and accurately identify, as well as describe, the purpose of individual wires and cables at a bundle's far extremity, it would be of great value. While the term “wireless” has become trendy and garners substantial attention, the fact remains, when it comes to the delivery of energy and information, “hard-wired” systems hold several advantages over wireless systems, particularly in the areas of system reliability and security.
Wires and cables offer great value in that they enable components in multiple locations to function together as a single system. However, such systems will only function properly if all electrical connections at both extremities are perfectly correlated and connected accordingly. Any installer of audio-video systems, who has “pulled” a bundle of wires through conduit, has experienced the frustration of having their identification tags torn off, then suddenly having no idea as to which wire goes where.
In addition to physically labeling (tagging) cables, there are several other contemporary approaches to cable identification. A widely used method is the color-coding the individual cables, so that each color represents a specific/unique purpose. Color-coding is an excellent method of wire or cable identification, if there are relatively few wires or cables involved. However, when the number of distinct wires/cables exceeds a dozen or so, color-coding may become impractical.
A continuity checker such as an ohmmeter may also be employed to identify individual wires within a bundle. The continuity method involves the use of a known reference ground, which may take any of several forms including metal conduit or a specified cable within a bundle. This methodology enables a particular cable at one extremity, electrically connected to a reference ground, to be identified at the other extremity, simply by determining which wire or cable exhibits electrical continuity when connected to that known reference ground. However, there is a limitation to this methodology. Each wire/cable that is to be traced must first be individually connected to the reference ground at one extremity, and then by a process of elimination, every wire/cable at the other extremity must also be examined for continuity with the reference ground until that particular wire/cable is found. Once a particular cable or wire is identified, the whole process must be repeated until every wire or cable in the bundle is identified. It should be noted that the identification of a cable, in itself, does not provide details of the cable's purpose, or intended connection point.
If there are a large number of wires/cables involved, or if the extremities are widely separated, identification by checking wire continuity can be time-consuming, laborious, and frustrating, particularly if the task is attempted by a single individual. Two people, working together, with one person at each extremity, and having a reliable means of communication, can greatly increase the speed of the wire/cable identification process, when using the continuity methodology.
A popular wire tracing methodology utilizes a specialized toner that induces an audible tone into a wire or cable, which may then be detected by a probe sensitive to that sound if placed in the vicinity of that wire or cable. This system works well when tracing the route of a cable or group of cables but is of limited use when trying to discriminate individual wires or cables within a bundle. As with the continuity methodology, details of the cables' purposes, or their intended connection points are not provided.